The IAAF World Junior Championships began on Monday in Eugene, Ore., the birthplace of Nike, Inc. If you've ever been to Eugene, you know that the only thing more conspicuous than green and gold is the superfluity of swooshes. But not this week.

The Register-Guard reports that all around Hayward Field—the same track where Nike cofounder Bill Bowerman coached and brand ambassador Steve Prefontaine ran—swooshes have been painted over, covered up, or taken down.

"All of the official IAAF partners have certain categories and rights, and Adidas happens to be one of them," said Vin Lananna, the president TrackTown USA, which lobbied to bring in World Juniors. "Providing a clean venue is a standard policy for major sports events."

The reason, of course, is money, of which Adidas has paid a lot to become the official partner of the International Association of Athletics Federations through 2019. IAAF sanctions the meet, and the host home must play by their rules. Adidas is in, Nike is out, and the meet goes on.

It's an interesting conflict: Lananna, the former track coach at Oregon and Stanford, has deep ties to Nike. But in his new role chairing TrackTown USA, the 2014 World Juniors is only his first victory for what he's said he hopes to accomplish. The more he succeeds in wooing international championships, the more he undercuts Nike's presence in the one place it considers itself beyond challenge.

That's not to say Nike will be completely un-represented: national federations have their own sponsorships, which are allowed to be displayed on uniforms, and Nike is the exclusive outfitter of USA Track & Field. Furthermore, athletes may choose their own footwear, either contracted or by predilection.

But this week, for the first time, Nike has been escorted out of its own house. If things continue to advance in Eugene, it won't be the last.